This invention relates to a signature collating and binding system with selectively controllable signature feeders, printers, and other apparatus.
Selective actuation of signature feeders by coded subscriber information is a known procedure which allows a single collating and binding system to simultaneously build different versions of a book of signatures, such as different editions of a magazine. A book of signatures, as is conventional, is any collection or group of signatures, each signature being composed of one or more sheets. The thickness of different books of signatures will randomly vary, depending on which feeders or inserters were actuated in response to the special interests of the subscribers. A book thickness caliper and circuit can continuously compare a detected book thickness with the book thickness which should have been selected under control of the coded information. Any error, as detected by the caliper or by sensors at the signature feeders, causes the defective book to be rejected, and a standard replacement book of signatures can be delivered to fill the empty space so as to prevent loss of synchronism with the coded information which also controls a label printer. An example of such a system is disclosed in Abram et al. U.S. Pat. No. 3,899,165 issued Aug. 12, 1975 and assigned to the present assignee.
The mailing labels which are placed on each book of signatures must correspond to the coded information which produced the customized books of signatures. This has been accomplished in the past by reading preprinted labels to develop the coded information, or by storing the coded information on magnetic tape which is read and later controls a printer which prints the mailing information directly on the books of signatures. Printers have also been associated with card inserters, located after the signature feeders and before the stitcher, to print custom information such as renewal information on a loose card before it is inserted in an already constructed book of signatures. The card can be bound in by a paster to prevent its being lost from the book of signatures associated therewith.
Defective books as detected by a caliper or by sensors associated with the signature feeders or other devices along the collating line have been automatically rejected. The resulting empty space on the collating conveyor may be filled, as taught in the Abrams et al. patent, by a replacement book of signatures. In other systems, a rejected book causes a new book of signatures to be automatically reordered. If preprinted labels are utilized, the label is rejected and a different means of printing the mailing label of the reordered book is used, such as an on-line printer. Rejected books can be reordered immediately if the zip code currently being produced can still be maintained; otherwise some special handling procedure is necessary such as to divert the reordered book when it reaches an output area. The entire collating system has been controlled by computers and/or programmable controllers as well as hardwired circuitry.
While the above systems are versatile in producing different editions of magazines or the like during a single production run, they suffer from a number of disadvantages. The contents of the different editions or variations are still controlled entirely by the signature which are loaded in the signature feeders. Since the number of signature feeders reaches a practical maximum, there is a limit to the variations which can be produced in concurrently run books of signatures.
The printing of labels and cards involve adapting conventional printers to the different requirements of a collating line. Often the labels and cards are printed off-line, and are then applied to a book of signatures or inserted therein. If the printer should malfunction, the resulting defective book may be sent out as there has been no error detection means corresponding to the calipers and limit switches which detect other types of errors on the collating line. However, an error in a mailing label can be more serious than an error such as the addition or deletion of a signature from a book of signatures.
Despite the use of computers and programmable controllers, considerable manual attention to the binding line is necessary. As the hoppers for signatures becomes low, they must be filled to allow continuation of the operation. This is especially critical for the standard book replacement feeder, in which the number of replacement books needed cannot be reasonably estimated in advance, as it will vary depending on the number of random rejects which occur during the collating and binding operation.
Also unsatisfactory has been the use of calipered thickness information to determine if a book of signatures should be rejected. Where the thickness can vary widely as occurs when various editions are run simultaneously, fixed tolerance limits results in the rejection of good books of signatures which calipered out of tolerance due to changes in atmospheric conditions or the like. This has resulted in rejection of unnecessary books, or in setting the tolerance limits for the caliper too wide and thus allowing some defective books to go undetected.